Snowmobiles are a common mode of transportation in the northernmost and southernmost regions of Earth where snow generally covers the ground all winter. Snowmobiles provide increased mobility to isolated communities by allowing people to travel great distances efficiently. In some communities, mobility is greater in the winter months than in the summer months because snowmobiles allow travel over snowy terrain where there is no reliable path when the snow melts in the summer. Snowmobiles have a profound impact in North America. The economic impact of snowmobiles in Canada and the United states is estimated at $34 billion each year. Snowmobiles provide the only source of income for some remote towns which rely on winter tourism. There are over 230,000 miles of developed snowmobile trails in North America.
Snowmobiles were originally intended as a winter utility vehicle that could be used where other vehicles could not go. Hunters and workers used snowmobiles to transport personnel and materials across snow-covered land and frozen lakes and rivers. Today, snowmobiles are also used for recreational purposes. Riders use snowmobiles for various types of racing, mountain climbing, and freestyle competitions wherein riders perform tricks while riding snowmobiles. Today, higher powered snowmobiles can reach speeds of 150 miles per hour (MPH), while drag racing snowmobiles can reach speeds of 200 MPH.
Snowmobiles turn by modifying the angle of the skis to force the snowmobile track to turn. Turning a snowmobile without leaning capability is unsafe because the skis dig into the snow to force the track one way or the other. When snowmobile skis dig into the snow to turn the snowmobile, centrifugal force can easily cause the snowmobile to roll. Fighting against centrifugal force rolling a snowmobile requires the rider to throw significant body weight in the opposite direction.
Snowmobiles are propelled by a continuous track or tracks at the rear driven by an engine. Snowmobiles have skis at the front to provide directional control. When the skis are angled left or right, the snowmobile is pushed in the direction the skis are angled by friction between the skis and the ground. The angle of a snowmobile's skis are controlled by a rider rotating a handlebar.
One goal of snowmobile manufacturers is to improve the performance of snowmobiles through technological advances. For example, snowmobiles can be designed to move faster, handle better through turns, or be easier to use. Manufacturers also strive to make snowmobiles as safe as possible. As a result of a snowmobile's inherent maneuverability, acceleration, and high-speed abilities, both skill and physical strength are required to operate a snowmobile. Losing control of a snowmobile can easily cause extensive property damage, injury, or death.
One way to improve the safety and performance of snowmobiles is by allowing the snowmobile to lean while turning. Previous attempts to create a snowmobile with leaning capability have failed because the mechanism for leaning the suspension is attached to the sprung mass of the snowmobile. Leaning vehicles use hydraulic shock absorbers that have a feeding tube coupled to the side of the shock. The feeding tube limits the range of motion of the hydraulic shocks used in leaning vehicles which limits the range of leaning a vehicle. The feeding tube is also an extra moving part that can experience wear and tear.